code: def ping(self, num_pings):
      children_outputs = []
      for _ in range(num_pings):
          children_outputs += [
              child.ping.remote() for child in self.children
          ]
      try:
          ray.get(children_outputs)
      except Exception:
          # Replace the children if one of them died.
          self.__init__(len(self.children), self.death_probability)
  
file_path: ray/release/nightly_tests/stress_tests/test_dead_actors.py
imports: import argparse
  import json
  import logging
  import numpy
  import os
  import sys
  import time
  import ray
label_desc: Use image node_id 2 for calling the Parent obj's underlying member method code with example usage: obj.ping(num_pings) without return types